Is this the one at Deer Valley in Phoenix? If so:
In 1997 I got an FAA ATP through them, on the back of my Australian ATPL. I was happy enough with my instructor (the chief pilot) even though, at only 2000hrs or so I had rather more hours than he - and he was one of the more experienced guys.
They had a zero-to-ATP (or 500 hrs or 1000hr or whatever it was) that relied on fresh students constantly coming thorugh the door. Effectively the students payed for their CPL & CFI then accrued hours teaching the next batch on the production line. Many were from overseas trying to take advantage of the somewhat cheaper & faster training available in the USA compared to their home country eg UK, India etc.
From overhearing various instructors chatting, the instructor motivation was more about where their next student was coming from (to keep the all important hours accruing), how long until they'd have to go home & whether or not they were far enough up the queue to get sufficient students/hours first (fair enough, I suppose but it means their focus isn't on what's best for the student), finding ways of extending their visa, trying to find the necessary multi hours needed for an MEI (so they could join the scrum trying to pick off the valuable but rarer multi flights). Whilst most of that is common amongst instructors in a group this was rather dominant. The most telling item stood out because of its lack: None of them seemed interested in discussing student progress, how to overcome a student's difficulty with an area of training, better/more efficient ways of training, finer points of rules & regulations understanding etc etc. These are things that are usually common amongst instructors, especially inexperienced ones. Also the disparagement of the company operation & management was similar in content to the negative things I've said here.
So generally training seemed to be done by new, or limited experience instructors who's goal was maximum flying hours for themselves. The overwhelming impression I got of the place was that it was a sausage factory that bred instructors with limited interest in instructing or doing what's best for students rather than the instructor's log book whilst the organisation was only interested in extracting $$$ from the customers.
Whilst what I've said is pretty harsh, it's not meant to reflect on any particular individual. Most people there were friendly. Just don't expect any leeway about payment. The policy was payment already made sufficient to cover the anticipated flight - or no flight. Never mind that that means you're taking all the risk by trusting them with your money.
In honesty I wouldn't recommend them **IF** they're still like that. Nor any other school that's similar, for that matter. I chose them because
A. they were about the only place in Phoenix who advertised the only US aviation magazine that reaches Australia, and
B. their ad. made a point of noting their expertise with foreign students, and
C. I had limited time available to plan for this because my primary travel purpose was family related in the UK and nothing to do with flying.
Not knowing how the US system works I was something of a neophyte. Knowing what I now know I wouldn't go back to them, and if I could do it again I'd go elsewhere.
I have no reason to doubt that if you choose to train there, you will gain the licences you set out to gain. I just think there are better alternatives.